What number makes this equation true? $148 = 754 - $
$148 = 754 -{{?}}$ ${148}$ ${754}$ $-?$ Let's start by subtracting hundreds from ${754}$ until we get as close to ${148}$ as possible without going below ${148}$. $\begin{aligned} {754} -100}=654\\\\ {654} -100}= 554\\\\ {554} -100}= 454\\\\ {454} -100}= 354\\\\ {354} -100}= 254\\\\ {254} -100}= 154 \end{aligned}$ If we subtract $6 \text{ hundreds}}$, or $6 00}$, we reach $154$. We cannot subtract any more hundreds without going below ${148}$. ${148}$ ${754}$ ${154}$ $-600$ Next, let's subtract tens from $154$ until we get as close to ${148}$ as possible without going below ${148}$. We cannot subtract any tens without going below ${148}$. Finally, how many ones should we subtract from $154$ to get to ${148}?$ $\begin{aligned} 154-{4} &= 150\\\\ 150-{2} &= 148 \end{aligned}$ We subtract ${6\text{ ones}}$. ${148}$ ${754}$ ${154}$ $-600$ $-6$ We subtracted $6 \text{ hundreds}}$ and ${6\text{ ones}}$ from ${754}$ to get to ${148}$. $6 00}+{6}={606}$ ${148}$ ${754}$ ${154}$ $-600$ $-6$ $-606$ $148 = 754 -{606}$